Jellyfish Facts

Jellyfish are fascinating creatures and there is a lot of interesting jellyfish facts. Did you for example know that jellyfish in some countries, including Japan, are considered a delicacy? This jellyfish fact is the reason behind a growing international market for dried jellyfish. The jellyfish is dried to prevent them from spoiling. A jellyfish spoils in a matter of hours if it isn’t dried, while dried jellyfish can be stored for weeks.

Another fascinating fact about jellyfish is that they don’t have any brain, heart, or bones. Some jellyfish have ways of detecting obstacles that can be compared to sight but they don’t have real eyes. It is a mystery how they can process the information from their “sight” since they doesn’t have any brain. They react directly on food and danger stimuli via nerve impulses without having any brain to process the impulses. Another fact about jellyfish and their bodies is that the body consists of over 95% water.

Jellyfish use tentacles with stinger cells to catch their prey, typically plankton and small fish. (The exact prey depends mainly on the size of the jellyfish.) The tentacles transport the prey they killed with their stingers to the mouth and the jellyfish promptly devours the animal. It is the same stinger cells that stings humans that ventures to close.

Jellyfish go through several stages during their lifecycle and the form that you usually associate with jellyfish, medusas, is only one of them. There is for instance a phase called planula, where the jellyfish is in a type of larval stage. The planulae eventually attach themselves to surfaces where they become polyps which later turn into to medusas.

A few other facts about jellyfish are:

Jellyfish fact: Jellyfish has been around for more than 650 million years which means that they outdate both dinosaurs and sharks.

Jellyfish fact: Different species of jellyfish can be found in all the worlds’ oceans. A type of jellyfish (that isn’t considered “true” jellyfish by science) can even be found in freshwater.

Jellyfish fact: A species of jellyfish, the Box jellyfish (sea wasp) kills more people than any other marine creature each year.

Jellyfish fact: The worlds largest known jellyfish can reach a diameter of 2.5 m / 8ft and its tentacles can grow to be half the length of a football field.

Jellyfish fact: Jellyfishes uses jet propulsion to make their way through to the oceans of the world. Some jellyfish are avid swimmers while other mostly drifts with the currents.

Jellyfish fact: Some species of jellyfish contains a lot of protein and are thought to be able to play a large role in ending hunger and malnutrition in poor areas around the world.

Jellyfish fact: Jellyfish are able to reproduce both sexually and asexually during different parts of their life cycle.

These where just a few facts about jellyfish and there is a lot more to discover about these mesmerizing creatures. I recommend that you read a few of our other articles about jellyfish if you want to learn more; they are all filled with fascinating facts about jellyfish.

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